. >> for those that were previously reduced, we are required by state law, proposition 8, to restore the assessed value to reflect the improving market value when the market begins to turn around. >> reporter: let's say you bought your house five years ago for $800,000. that's considered your prop 13 base even if your value goes way up, your assessed value will go up no more than 2% a year. but prop 8 allows the county to reassess your property to reflect a lower market value, which means if your value declines, you'll get a lower tax bill. but here's the catch. if your home value jumps back up but it's still worth less than you paid, you could see a big property tax increase in this case 6.9%. >> it might be 2.1%. it might be 10% depending upon the market that's occurring in that specific neighborhood. >> reporter: while that increase may be a painful surprise, the county assessor larry stone says there's a silver lining. >> for everyone 1% increase in the property taxes, the property owner gains 99% in improved equity. >> reporter: he also says only 10% of the residential property